Establishing reference values for aortic dimensions in the general Indian population and implications for global standards.

Background: The dimensions of the aorta play a crucial role in cardiovascular health, serving as a determinant of normalcy and a marker for pathological conditions such as aortic aneurysms and dissections. Extensive research has been conducted on the ascending aortic dimensions in the Western population, which forms the basis of the current aortic surgical guidelines. However, there remains a paucity of data specifically focused on the Indian population, which is essential for accurate diagnosis, risk stratification, and management of aortic diseases in the Indian context. This paper aims to describe the general aortic size distribution in the general Indian population. Methods: To study the aortic size in the Indian general population, we included all consecutive individuals who underwent a computed tomography (CT) scan between January 2022 and December 2022. Patients under the age of 18 years, those with cardiovascular comorbidities, and those with any aortic segment measuring > 45 mm were excluded from the analysis. The maximum aortic diameters were measured at predefined levels (aortic root, ascending aorta, aortic arch, proximal descending aorta, and the abdominal aorta). Results: Our study comprised 891 individuals with a mean age of 51.9 years, of which 41.5% were female. The mean ascending aortic diameter of all subjects was 29.3 ± 3.9 mm and was significantly smaller in women (28.7 ± 4.0 mm) as compared to men (29.8 ± 3.8 mm), even after correcting for age, body mass index (BMI), and body surface area (BSA). The proportion of subjects with an ascending aorta < 3.5 cm was 93.5%, that of subjects with 3.5-3.9 cm was 6.2%, and that of subjects with 4.0-4.4 cm was 0.3%. Conclusions: The general aortic dimension in the Indian population is deceptively small, most commonly < 3.5 cm. The ascending aorta is significantly smaller in the female population, also after correcting for age, BMI, and BSA. This study provides evidence to question current recommendations in the aortic guidelines for surgical intervention at 5-5.5 cm for the Indian population and whether a distinction should be made for the female patients. Graphical Abstract: Supplementary Information: The online version contains supplementary material available at 10.1007/s12055-025-02173-6.